It is a current trend in vehicles to apply ACC (Adaptive Cruise Control) to detect the distance to a front vehicle. CDMs (Chassis Dynamometers) are also provided to vehicles to alarm a driver when a collision with the front vehicle is likely.
ACCs and CDMs typically use radar to detect vehicles in the front area. If the radar device is positioned incorrectly, even at a slight angle, its performance suffers. The radar devices are typically aligned using lasers. However, several problems arise from the use of lasers. For example, the front of the vehicle must be parallel with the surface on which the laser equipment is mounted and the central axes of the laser and the vehicle must be aligned, which is a difficult undertaking.